Operations and Maintenance

What Are the Disinfection Requirements for Commissioning Piping or Equipment in Potable Water Service?


Arizona Department of Environmental Quality (ADEQ) Bulletin No. 8, "Disinfection of Water Systems," specifies the methodology and requirements for the disinfection of new piping and equipment. Bulletin No. 8 also discusses disinfection using chlorination as well as safety measures and emergency disinfection procedures.

In addition to the disinfection procedures specified in ADEQ Bulletin No. 8, the following American Water Works Association (AWWA) standards may be used:
  • AWWA Standard C651-05 - "Disinfecting Water Mains"
  • AWWA Standard C653-03 - "Disinfection of Water Treatment Plants"
  • AWWA Standard C654-03 - "Disinfection of Wells"
To verify effective disinfection, bacteriologic samples must be collected from the same locations at the time intervals and frequency specified by the above standards. The samples must be analyzed by a laboratory within 24 hours of collection of the sample. Samples should be maintained at or near 4oC until they are sent to the testing laboratory for testing.

When the laboratory provides written confirmation of the absence of total coliform bacteria in all samples the piping or equipment is considered to be disinfected. If any of the samples fail then the disinfection process shall be repeated per the above standards until the samples pass.

Water shall not be sent to the distribution system until:
  • The piping or equipment has been disinfected.
  • Certified copies of the laboratory analysis reports have been submitted to the Water and Wastewater Treatment Program.
  • Written authorization approving the release of water to the distribution system has been received from the Water and Wastewater Treatment Program.

What Are the Start-Up Requirements for a New Treatment Facility or System?


A new or modified treatment facility or system utilizing a complex or novel treatment process or very large facilities such as surface water treatment plants require the submission of a Start-up Plan for review and approval by the Water and Wastewater Treatment Program. A Start-up Plan may not be required for a simple treatment process or for a small facility as the start-up requirements may be specified on the Approval To Construct certificate. Start-up requirements will be determined on a project-by-project basis by the Water and Wastewater Treatment program.

Prior to start-up the following action items must be completed:
  • Submission of an Approval Of Construction Application
  • Submission of an Engineer's Certificate Of Completion Form
  • An approved Start-up Plan (if required)
  • A draft O&M manual (minimum content is startup, shutdown and emergency procedures)
  • Certified bacteriologic lab reports
  • Construction test documentation (pressure or leak tests, etc.)
  • Instrument calibration sheets for instruments to be used during Initial Testing
  • A final construction inspection of the treatment facility or system by Water and Wastewater Treatment Program staff
Additional items may be required by the Water and Wastewater Treatment Program prior to start-up. When the action items are complete an Approval To Commence Operations certificate is issued by the Water and Wastewater Treatment Program to allow Initial Testing of the treatment facility or system to proceed.

Initial Testing consists of two distinct testing phases: Validation Testing and Commissioning Testing. Validation Testing commences immediately upon start-up of the system. Validating Testing is conducted per the methods and procedures described in the approved Start-up Plan or as stipulated on the Approval To Commence Operations certificate. Validation Testing provides verification that the treatment process is working as designed. During Validation Testing finished water from the facility or system must be properly disposed and cannot be released to the water distribution system.

After Testing


When Validation Testing is successfully completed, the testing results are submitted to the Department by the certified operator under a signed cover letter stating that the operator personally witnessed the testing and that the results are accurate to the best of his/her knowledge. After reviewing and approving the results, the Department authorizes the treatment facility or system to immediately go into the Commissioning Testing phase. At this point finished water may be released from the facility or system into the distribution system.

Commissioning Testing commences immediately after Validation Testing. Commissioning Testing is conducted per the methods and procedures described in the approved Start-up Plan or as stipulated on the Approval To Commence Operations certificate. Commissioning Testing verifies the performance of the treatment process in normal operation.

When Commissioning Testing is successfully complete, the testing results are submitted to the Department by the certified operator under a signed cover letter stating that the operator personally witnessed the testing and that the results are accurate to the best of his/her knowledge.

Upon successful completion of Validation and Commissioning Testing, the following documentation must be submitted to the Department:
  • An Engineer's Certificate Of Completion
  • Performance testing data, laboratory analyses and evaluation reports as required per the previously approved Start-up Plan or as stipulated on the Approval To Commence Operations certificate
  • A full set of sealed, engineered as-built design drawings
The Water and Wastewater Treatment Program will review and approve the submitted material and issue an Approval of Construction certificate.

What Are the Reporting Requirements for Treatment Facilities?


For wastewater treatment facilities monthly operations and maintenance (O&M) reports are submitted on a monthly basis for the life of the facility. The format and content of the report is determined when a new or modified facility is initially commissioned. The format and content of the report may be changed at the Department's discretion if the physical configuration of the plant or the treatment process is modified. The monthly O&M report is reviewed by Water and Wastewater Treatment Program staff to ensure that the wastewater treatment facility is being operated and maintained in a safe and efficient manner and is in compliance with the rules and regulations.

For water treatment facilities the reporting requirements and review criteria are defined by the Safe Drinking Water Act and any special requirements established by MCESD's Drinking Water Program. The reporting requirements and the format and content of any reports are determined when a new facility is initially commissioned. The reporting requirements and the format and content of the report may be changed at the Department's discretion if the physical configuration of the plant or the treatment process is modified. All reports are reviewed by Drinking Water Program staff to ensure that the water treatment facility is being operated and maintained in a safe and efficient manner and is in compliance with the rules and regulations.

Do Wastewater & Reclaimed Water Spills Have to Be Reported?


Wastewater or reclaimed water spills shall be immediately reported to the Maricopa County Environmental Services Department by the operator of the wastewater treatment or reclaimed water facility or system. The Maricopa County Environmental Health Code (MCEHC) does not allow incidental releases of wastewater that may be allowed by Capacity, Management, Operation and Maintenance (CMOM) Permits. All releases of wastewater or reclaimed water are considered to be spills per Chapter 2, Section I, Regulation 2, Subsection B of the MCEHC.